by Sarah Lynch, Special for USA TODAY

by Sarah Lynch, Special for USA TODAY

CAIRO - Chaos spewed around a central Cairo mosque Saturday as the death toll from weekend violence climbed and authorities considered disbanding the Muslim Brotherhood.

In Ramses Square, Egyptian security forces stormed the Al-Fateh mosque, where protesters had remained overnight, barricading themselves inside. The mosque had been serving as a makeshift hospital and morgue after Friday's violent clashes.

On Saturday, gunmen ascended the mosque's minaret and opened fire on security forces and civilians below, state news agency MENA reported. Video footage broadcast on local television showed security forces shooting back. Later in the afternoon, police dispersed protesters at the mosque, MENA reported.

Security officials told the Associated Press that officers raided the mosque out of fear the Muslim Brotherhood planned to set up a new sit-in protest camp. The officials spoke on the condition of anonymity in line with regulations.

The fresh unrest caps a week of widespread and unpredictable violence that killed more than 800 nationwide after security forces crushed two protest camps in Cairo on Wednesday with bulldozers, gunfire and tear gas and protesters again took to the streets Friday, clashing with police.

The death toll from Friday's clashes rose to 173, Egyptian government spokesman Sherif Shawki said Saturday. The Health Ministry said at least 683 were killed Wednesday as security forces cleared the sit-ins and retaliatory attacks and clashes billowed across the country.

On Saturday, the brother of al-Qaeda chief Ayman Al-Zawahri was arrested and moved to a heavily guarded prison, MENA reported. Mohammed Al-Zawahri, who lives in Egypt, follows a hard-line Islamic ideology and was allied with the ousted Islamist president, Mohammed Morsi.

In another sign of a widening crackdown on Egypt's Islamists, Shawki said Saturday that interim Prime Minister Hazem el-Beblawi assigned the Social Solidarity Ministry to study the legal possibilities of dissolving the Brotherhood.

The 85-year-old movement has won in every election since the 2011 ouster of Hosni Mubarak, but over the past six weeks, many of its leaders and members have been arrested.

Historically, the state and Brotherhood have been at odds for decades, with many members having spent years in jail under Mubarak.

Egypt is facing "war by the forces of extremism" and will confront it with "security measures within the framework of law," Mostafa Hegazy, adviser to Egypt's interim president, said in a press conference Saturday.

Morsi supporters, however, blamed the government for starting ongoing violence that began Friday afternoon as Morsi supporters marched to Ramses Square, now the center of conflict in central Cairo.

"We don't have weapons ... and they are shooting us." said Jamal Salam as he marched to the square in a Brotherhood-incited "Friday of Anger."

Scenes of chaos gripped the city as heavy gunfire resounded across the capital Friday.

"People are afraid," said Sabr Agaya, who lives and works in Giza near the pyramids. "They are afraid from people dying downtown. They look at the TV, and they're so afraid."